what is the procedure to install a downgrade license ? the think is to downgrade vcenter standard to vcenter essential kit plus to avoid any issues in the cluster. the vcenter version is 6.5.
If you've downgraded vCenter Standard to vCenter Essentials, you cannot use the Essentials license to manage non-Essentials ESXi hosts. This is most likely the reason you're seeing the error on your host below. Essentials licenses are a pair--host and vCenter. You cannot separate the two.
That depends on you and your goals and how much you have to spend. There is no recommended license type of ESXi without knowing these factors, but whatever you choose you can't mix and match Essentials with non-Essentials licenses.
